xref: /freebsd/sys/vm/vm_unix.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 1988 University of Utah.
3  * Copyright (c) 1991, 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * the Systems Programming Group of the University of Utah Computer
8  * Science Department.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$
35  *
36  *	@(#)vm_unix.c	8.1 (Berkeley) 6/11/93
37  */
38 
39 #include "opt_compat.h"
40 
41 /*
42  * Traditional sbrk/grow interface to VM
43  */
44 
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 #include <sys/param.h>
49 #include <sys/lock.h>
50 #include <sys/mutex.h>
51 #include <sys/proc.h>
52 #include <sys/racct.h>
53 #include <sys/resourcevar.h>
54 #include <sys/sysent.h>
55 #include <sys/sysproto.h>
56 #include <sys/systm.h>
57 
58 #include <vm/vm.h>
59 #include <vm/vm_param.h>
60 #include <vm/pmap.h>
61 #include <vm/vm_map.h>
62 
63 #ifndef _SYS_SYSPROTO_H_
64 struct obreak_args {
65 	char *nsize;
66 };
67 #endif
68 
69 /*
70  * MPSAFE
71  */
72 /* ARGSUSED */
73 int
74 sys_obreak(td, uap)
75 	struct thread *td;
76 	struct obreak_args *uap;
77 {
78 	struct vmspace *vm = td->td_proc->p_vmspace;
79 	vm_map_t map = &vm->vm_map;
80 	vm_offset_t new, old, base;
81 	rlim_t datalim, lmemlim, vmemlim;
82 	int prot, rv;
83 	int error = 0;
84 	boolean_t do_map_wirefuture;
85 
86 	datalim = lim_cur(td, RLIMIT_DATA);
87 	lmemlim = lim_cur(td, RLIMIT_MEMLOCK);
88 	vmemlim = lim_cur(td, RLIMIT_VMEM);
89 
90 	do_map_wirefuture = FALSE;
91 	new = round_page((vm_offset_t)uap->nsize);
92 	vm_map_lock(map);
93 
94 	base = round_page((vm_offset_t) vm->vm_daddr);
95 	old = base + ctob(vm->vm_dsize);
96 	if (new > base) {
97 		/*
98 		 * Check the resource limit, but allow a process to reduce
99 		 * its usage, even if it remains over the limit.
100 		 */
101 		if (new - base > datalim && new > old) {
102 			error = ENOMEM;
103 			goto done;
104 		}
105 		if (new > vm_map_max(map)) {
106 			error = ENOMEM;
107 			goto done;
108 		}
109 	} else if (new < base) {
110 		/*
111 		 * This is simply an invalid value.  If someone wants to
112 		 * do fancy address space manipulations, mmap and munmap
113 		 * can do most of what the user would want.
114 		 */
115 		error = EINVAL;
116 		goto done;
117 	}
118 	if (new > old) {
119 		if (!old_mlock && map->flags & MAP_WIREFUTURE) {
120 			if (ptoa(pmap_wired_count(map->pmap)) +
121 			    (new - old) > lmemlim) {
122 				error = ENOMEM;
123 				goto done;
124 			}
125 		}
126 		if (map->size + (new - old) > vmemlim) {
127 			error = ENOMEM;
128 			goto done;
129 		}
130 #ifdef RACCT
131 		if (racct_enable) {
132 			PROC_LOCK(td->td_proc);
133 			error = racct_set(td->td_proc, RACCT_DATA, new - base);
134 			if (error != 0) {
135 				PROC_UNLOCK(td->td_proc);
136 				error = ENOMEM;
137 				goto done;
138 			}
139 			error = racct_set(td->td_proc, RACCT_VMEM,
140 			    map->size + (new - old));
141 			if (error != 0) {
142 				racct_set_force(td->td_proc, RACCT_DATA,
143 				    old - base);
144 				PROC_UNLOCK(td->td_proc);
145 				error = ENOMEM;
146 				goto done;
147 			}
148 			if (!old_mlock && map->flags & MAP_WIREFUTURE) {
149 				error = racct_set(td->td_proc, RACCT_MEMLOCK,
150 				    ptoa(pmap_wired_count(map->pmap)) +
151 				    (new - old));
152 				if (error != 0) {
153 					racct_set_force(td->td_proc, RACCT_DATA,
154 					    old - base);
155 					racct_set_force(td->td_proc, RACCT_VMEM,
156 					    map->size);
157 					PROC_UNLOCK(td->td_proc);
158 					error = ENOMEM;
159 					goto done;
160 				}
161 			}
162 			PROC_UNLOCK(td->td_proc);
163 		}
164 #endif
165 		prot = VM_PROT_RW;
166 #ifdef COMPAT_FREEBSD32
167 #if defined(__amd64__)
168 		if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32))
169 			prot |= VM_PROT_EXECUTE;
170 #endif
171 #endif
172 		rv = vm_map_insert(map, NULL, 0, old, new, prot, VM_PROT_ALL, 0);
173 		if (rv != KERN_SUCCESS) {
174 #ifdef RACCT
175 			if (racct_enable) {
176 				PROC_LOCK(td->td_proc);
177 				racct_set_force(td->td_proc,
178 				    RACCT_DATA, old - base);
179 				racct_set_force(td->td_proc,
180 				    RACCT_VMEM, map->size);
181 				if (!old_mlock && map->flags & MAP_WIREFUTURE) {
182 					racct_set_force(td->td_proc,
183 					    RACCT_MEMLOCK,
184 					    ptoa(pmap_wired_count(map->pmap)));
185 				}
186 				PROC_UNLOCK(td->td_proc);
187 			}
188 #endif
189 			error = ENOMEM;
190 			goto done;
191 		}
192 		vm->vm_dsize += btoc(new - old);
193 		/*
194 		 * Handle the MAP_WIREFUTURE case for legacy applications,
195 		 * by marking the newly mapped range of pages as wired.
196 		 * We are not required to perform a corresponding
197 		 * vm_map_unwire() before vm_map_delete() below, as
198 		 * it will forcibly unwire the pages in the range.
199 		 *
200 		 * XXX If the pages cannot be wired, no error is returned.
201 		 */
202 		if ((map->flags & MAP_WIREFUTURE) == MAP_WIREFUTURE) {
203 			if (bootverbose)
204 				printf("obreak: MAP_WIREFUTURE set\n");
205 			do_map_wirefuture = TRUE;
206 		}
207 	} else if (new < old) {
208 		rv = vm_map_delete(map, new, old);
209 		if (rv != KERN_SUCCESS) {
210 			error = ENOMEM;
211 			goto done;
212 		}
213 		vm->vm_dsize -= btoc(old - new);
214 #ifdef RACCT
215 		if (racct_enable) {
216 			PROC_LOCK(td->td_proc);
217 			racct_set_force(td->td_proc, RACCT_DATA, new - base);
218 			racct_set_force(td->td_proc, RACCT_VMEM, map->size);
219 			if (!old_mlock && map->flags & MAP_WIREFUTURE) {
220 				racct_set_force(td->td_proc, RACCT_MEMLOCK,
221 				    ptoa(pmap_wired_count(map->pmap)));
222 			}
223 			PROC_UNLOCK(td->td_proc);
224 		}
225 #endif
226 	}
227 done:
228 	vm_map_unlock(map);
229 
230 	if (do_map_wirefuture)
231 		(void) vm_map_wire(map, old, new,
232 		    VM_MAP_WIRE_USER|VM_MAP_WIRE_NOHOLES);
233 
234 	return (error);
235 }
236 
237 #ifndef _SYS_SYSPROTO_H_
238 struct ovadvise_args {
239 	int anom;
240 };
241 #endif
242 
243 /*
244  * MPSAFE
245  */
246 /* ARGSUSED */
247 int
248 sys_ovadvise(td, uap)
249 	struct thread *td;
250 	struct ovadvise_args *uap;
251 {
252 	/* START_GIANT_OPTIONAL */
253 	/* END_GIANT_OPTIONAL */
254 	return (EINVAL);
255 }
256